--- title: "NanoDiffract test platform" url: "" featureImage: "" short: "nanodiffract" category: "platform" ai: "" order: "01" year: "2021 – now" tags: ["python", "pytest", "c", "c++", "postgresql", "azure devops", "rhel", "qt"] --- My day job, since 2021: build and test engineering for NanoDiffract, Onto Innovation's decades-old, 2M+ line C++ optical metrology software, in a Windows shop. The work is finding the pain points in how the software gets built and tested, and engineering them away. - **The regression-testing system**, designed and built over five years. It's a pytest-based tool that generates reference results for each build, stores them in PostgreSQL, and runs PR validation and post-merge regressions on the compute cluster. Every NanoDiffract engineer relies on it. - **A desktop GUI for it** (PySide6, Cythonized), now in use at five leading chipmakers and rolling out to every Onto customer. - **Tooling on top of it**: automated bisection across official builds that finds the build behind a result change in minutes, where it used to be a manual, build-by-build hunt; a benchmark harness with statistical significance testing; and a memory monitor, a small HTTP server in C on each cluster node that the head node polls for memory use. - **The cluster itself**: automated recovery of wedged and lost nodes for the application developers, and once, two weeks of tracking erratic behavior on 80 nodes down to a faulty port on the server rack. - **The build infrastructure**: I provision and maintain the build machines, write the teams' Azure DevOps pipelines, led compiler and dependency upgrades and a build-system redesign, and cleared about 7,000 compiler warnings by hand. - **A Python C extension** reimplementing the software's neural net inference, so the ML engineers could analyze the results. The code isn't public, so there's nothing to link to here.

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<section class="source"> <header class="source-head"> <a href="https://github.com/mas-4/standingwater-flat/blob/main/src/${source.path}">${source.path}</a> <span>${source.lines} lines</span> </header> <pre class="listing"><code>${source.code}</code></pre> </section>

← all projects

platform2021 – now

NanoDiffract test platform

My day job, since 2021: build and test engineering for NanoDiffract, Onto Innovation's decades-old, 2M+ line C++ optical metrology software, in a Windows shop. The work is finding the pain points in how the software gets built and tested, and engineering them away.

The regression-testing system, designed and built over five years. It's a pytest-based tool that generates reference results for each build, stores them in PostgreSQL, and runs PR validation and post-merge regressions on the compute cluster. Every NanoDiffract engineer relies on it.
A desktop GUI for it (PySide6, Cythonized), now in use at five leading chipmakers and rolling out to every Onto customer.
Tooling on top of it: automated bisection across official builds that finds the build behind a result change in minutes, where it used to be a manual, build-by-build hunt; a benchmark harness with statistical significance testing; and a memory monitor, a small HTTP server in C on each cluster node that the head node polls for memory use.
The cluster itself: automated recovery of wedged and lost nodes for the application developers, and once, two weeks of tracking erratic behavior on 80 nodes down to a faulty port on the server rack.
The build infrastructure: I provision and maintain the build machines, write the teams' Azure DevOps pipelines, led compiler and dependency upgrades and a build-system redesign, and cleared about 7,000 compiler warnings by hand.
A Python C extension reimplementing the software's neural net inference, so the ML engineers could analyze the results.

The code isn't public, so there's nothing to link to here.